Process for the production of 4-amino-6,7-dimethoxy-2-[4-(furo-2-yl)-piperazin-1-yl]-quinazoline and physiologically compatible salts thereof

Abstract

The invention relates to a new multistage process for the production of 4-amino-6,7-dimethoxy-2-[4-(furo-2-yl)-piperazin-1-yl]-quinazoline corresponding to the following formula ##STR1## and physiologically compatible salts thereof, which gives better yields and uses less expensive and more reactive materials than known processes. The intermediate product formed in this process, N"-cyano-N'-(3,4-dimethoxyphenyl)-O-phenylisourea, shows antihypertensive activity on its own.

We claim: 
     
       1. N"-cyano-N'-(3,4-dimethoxyphenyl)-O-phenylisourea corresponding to the following tautomeric formulae ##STR22##